Is there any way to put this delicately? Men, when they have children, get fatter. We’ve known this for a while, and now the first nationally representative sample confirms it. In a study published in the American Journal of Men’s Health, researchers at Northwestern tracked the body mass index of 10,623 fathers and nonfathers over several years. The typical 6-foot-tall man gained an average of 4.4 pounds in the years after having a child; the new dad who did not live with his child...